Katarakt.Information

What is a cataract?

A cataract is a clouding of the eye's natural lens. Vision deteriorates gradually, often over years, before it really becomes noticeable. The good news: a cataract is fully treatable. Around 150,000 cataract operations are carried out in Austria each year, with a success rate of over 95 per cent.

What happens in your eye?

Behind the pupil sits the eye's lens, a transparent structure roughly the size of a lentil. Its single task is to focus light sharply onto the retina. It works like the optics of a camera and needs absolute clarity to do its job.

In a cataract, the protein molecules in the lens clump together. Picture how egg white turns milky and opaque when heated: the same process, only in slow motion over years. The lens loses its transparency, light is scattered instead of focused, and the result is blurred vision with marked sensitivity to glare.

Anatomical cross-section of the human eye showing the cornea, iris, lens and retina
Illustration of a clear, healthy lens of the eye
Healthy lens

Clear and transparent. Light is focused sharply onto the retina and the image is crisp.

Illustration of a lens clouded and discoloured brownish by a cataract
Lens with a cataract

Protein deposits scatter the light. The image becomes blurred, pale and sensitive to glare.

How do people with a cataract see?

Move the slider: cataract vision on the left, normal vision on the right.

With a cataract
Normal vision

Do you have these signs?

A cataract develops gradually. Tick what applies to you and you will receive an assessment straight away.

Select the points that apply to you.

Which forms are there?

Age-related cataract (cataracta senilis)

Accounting for over 95 per cent of all cases, this is the most common form. From the age of 50 it becomes steadily more frequent: around one in two people aged 70 to 80 is affected, and more than seven in ten of those over 80.

Depending on where the clouding sits, three subtypes are distinguished. A nuclear cataract affects the core of the lens and, alongside blurring, often gives vision a yellowish tint. A cortical cataract shows spoke-like opacities in the outer layer of the lens. A posterior subcapsular cataract sits directly behind the core and causes reading difficulties and strong glare particularly early on.

What promotes a cataract?

Age is the main factor, but not the only one. Some risks can actually be influenced.

Cannot be influenced
  • Age from 60 onwards, the risk rises markedly after that
  • Genetic predisposition, clustering in families is well documented
  • Sex, women are affected slightly more often because of their longer life expectancy
Can be influenced
  • UV radiation, sunglasses with UV-400 protection shield the lens in the long term
  • Smoking doubles to triples the risk, and quitting lowers it again
  • Diabetes, good blood-sugar control also lowers the cataract risk
  • Long-term cortisone therapy, discuss with your treating doctor whether alternatives are possible
over 70%
of people over 80 are affected
150,000
operations in Austria each year
over 95%
success rate for uncomplicated surgery
15 min
average duration of the operation

Do I need surgery straight away?

No. There is no fixed threshold at which an operation becomes compulsory. What matters is whether the cataract restricts your daily life: driving, reading, watching television, recognising faces. As long as these still work well, many patients can simply monitor the situation with regular check-ups.

What does not work: pinning your hopes on drops or medicines. There is no remedy that reverses or halts a clouding of the lens. The only effective treatment is surgery.

Waiting too long can increase the risks

A very mature cataract is technically harder to operate on and can raise the pressure inside the eye. Restricted vision also increases the risk of falls. A known cataract should therefore be checked regularly.

Not sure whether it is a cataract?

Only an eye examination can settle the question. Find a specialist near you who will examine your eyes and advise you.

Find a specialist near you

Frequently asked questions

Download the patient info sheet
Cataract essentials on one page (PDF, A4, in German)
PDF
Medically reviewed information
Last updated: April 2026 Sources: Austrian Ophthalmological Society (ÖOG), gesundheit.gv.at, WHO Global Data on Visual Impairments